套索人工肌肉的实现及其在穿戴式康复装置中的应用

Light and soft man-machine interface structures are widely needed for new-designed comfortable walking assisted devices for the elder people and wearable rehabilitation/training devices for the wounded people. Based on the properties of tendon-sheath transmission and Hill muscles model, this application proposed a new type of artificial muscles, in which the contracting unit (CU) is composed of a controllable clamp with the cooperation of the driving effort of the tendon-sheath, and the series elastic unit (SEU) and the parallel elastic unit (PEU) are made of elastic springs. This new artificial muscles can work similar as real animal muscles with similar elasticity and compliance. In this work, the realization of the 3 typical contraction modes of the animal muscles using these new artificial muscles, reduction of human joint activating muscles, transmission properties of antagonists with this new artificial muscle pairs, and the precise tracking control of the joints actuated by this new artificial muscle pairs will be studied. For designing more comfortable wearable assisting devices, optimization of the tendon-sheath path arrangement and the joint structure will also be conducted. For minimizing the energy consumption, passive walking and harmony walking theory will be studied based on elasticity of the new artificial muscles. The results of this research will provide a new transmission method for walking assisting devices and rehabilitation devices with agility, efficiency, comfort and safety.

新型的、具有良好舒适性的老年助行器和伤后穿戴式康复训练器，需要轻软的人机结合形态。本申请提出利用索套细长、柔软的传动特性，采用Hill肌肉模型体制，由可控夹紧头和套索驱动的组合实现收缩元、用弹簧实现串联和并联弹性元，构建“套索人工肌肉”，其可实现人体肌肉的全部收缩模式，具有类似肌肉的弹性和平顺性。课题将研究人体肌肉三种典型收缩模式的套索人工肌肉实现方法；基于生物运动力学分析的人体关节驱动肌肉群的简化与等效；“套索人工肌肉”的对抗应用及在此模式下机电关节的位移与力矩传递特性；对抗“套索人工肌肉”驱动关节的位移与力矩协同精密跟踪控制；助力/康复装置关节驱动形式优化与套索布置路径优化；基于套索人工肌肉的串/并联弹性，研究穿戴装置与人体的谐振运动和储放能节能行走机构设计问题。项目的成果将可为新型穿戴式助力/康复装置设计提供一种实用的、灵活高效、安全舒适的传动方式。

老年助行以及伤后康复训练迫切需要新型、便携、安全舒适的穿戴型外骨骼装置，轻型、可控、柔顺的人工肌肉驱动器对于解决这一需求具有重要的研究意义。本课题基于Hill肌肉模型设计了新型套索人工肌肉，利用电磁铁驱动的可控夹头和套索驱动机构构造肌肉的主动收缩单元，利用线性弹簧分别构造肌肉的串联弹性和并联弹性，其可实现类似肌肉的收缩力-长度-速度特性以及肌肉的典型收缩模式。利用OpenSim及开源模型Gait2392_Simbody仿真分析，得到下肢主要肌肉群的激励度以及收缩量，对下肢肌肉群进行了简化并根据简化结果对套索人工肌肉进行了仿生学布置。基于生物肌肉对抗肌的形式，搭建了复式套索人工肌肉驱动机构，并基于套索静态传递模型进行了复式套索人工肌肉传递特性建模研究，得到了力和位移传递特性模型，通过实验验证了模型的准确性。为解决套索人工肌肉驱动关节的力控制问题，研究了套索人工肌肉收缩力与总伸长量的关系模型，基于此模型提出了一种无拉力传感器的肌肉收缩力反馈控制方法，比传统的基于拉力传感器的反馈控制更精确。设计了滑模控制算法解决套索人工肌肉驱动关节的位移跟踪控制并在外骨骼装置上进行了实验验证。通过减少套索弯曲全曲率研究了套索传递路经优化问题，对髋关节、膝关节以及踝关节的套索传动路径进行了优化。研究了人体下肢关节运动特性和步行周期特性，计算了各关节的力矩和功率消耗曲线，研究了人体持续行走所需的最小能耗以及能量补充的时机与大小作为人工肌肉能量存储设计的依据。基于人体下肢运动机理研究以及套索人工肌肉模型理论研究，设计了套索人工肌肉驱动全下肢康复外骨骼并建立了其动力学模型，在此基础上提出了被动跟踪以及主动训练控制算法，完成了人机协同运动跟踪实验以及基于人机交互力反馈的主动行走助力实验。